المجلة الدولية للعلوم والتقنية

Lagrange Interpolation and divided difference are the two methods to study in this paper. To apply them for the data that obtained from the civil registrations office. To show the prophesying of changing number of families groups. The numbers of the family groups has been shown. By the results in years 2018, 2019, and 2024. The Lagrange interpolation method appears to have bean accurate and precise results. Keywords: Lagrange Interpolation – Divided Difference Numbers of Families Groups.